Valve device

Abstract

A valve device has a valve housing (10), in which fluid ports (P, A, T) are provided and in which at least one valve piston (12, 14) can be moved longitudinally. The valve piston either separates at least two of the fluid ports (P, A, T) from one another or interconnects them as a function of its travel position. At least one latching device (16, 18) is provided for each valve piston (12, 14) for the detachable fastening of the respective valve pistons (12, 14) in one of its travel positions. Each latching device has at least one latching means (20), which can be brought into a latching position (22). As part of the respective latching devices (16, 18) for detachably fastening the respective valve pistons (12, 14), at least one control body (24) t can be moved independently of the respective valve pistons (12, 14), which control body is set up such that, in at least one blocking position, it prevents the relevant latching means (20) disposed in the latching position (22) from leaving the latching position (22) by blocking the latching means (20).

The invention claimed is: 
     
       1. A valve device, comprising:
 a valve housing having fluid ports therein; 
 a first valve piston movable longitudinally in the valve housing between positions separating at least two of the fluid ports from one another or interconnecting at least two of the fluid ports as a function of a travel position of the first valve piston; and 
 a first latch connected to the first valve piston detachably fastening the first valve piston in one of travel positions of the first valve piston, the first latch having a first latching part movable into and out of a first latching position and having a first control body movable independently of the first valve piston, the first control body being movable to a first blocking position preventing the first latching part disposed in the first latching position from leaving the first latching position by blocking the first latching part, the first control body being guided displaceable between the first blocking position and a first release position in a first hollow guide sleeve guided for travel between a first sleeve blocking position and a first sleeve release position in a second control body of the first latch, the second control body having an abutment. 
 
     
     
       2. The valve device according to  claim 1  wherein
 the first latching part contacts the abutment in the first latching position with the first control body in the first blocking position. 
 
     
     
       3. The valve device according to  claim 1  wherein
 when the first control body is disposed in the first release position, the first latching part is released for disengagement from the abutment. 
 
     
     
       4. The valve device according to  claim 1  wherein
 the first latching part is movably guided between the first latching position and a first release position of the first latching part in a wall of a hollow guide sleeve of the first latch, a radial wall thickness of the hollow guide sleeve being smaller than a largest diameter of the first latching part. 
 
     
     
       5. The valve device according to  claim 1  wherein
 the hollow guide sleeve, when the first latching part is disposed in the first latching position, is disposed in a sleeve blocking position and is blocked by the first latching part for a travel motion in a second control body in at least one direction of travel, at a same time the first control body is released for a travel motion in the hollow guide sleeve. 
 
     
     
       6. The valve device according to  claim 5  wherein
 the hollow guide sleeve, when the first latching part is disposed in a release position of the first latching part, entrains the first latching part and/or the first control body is secured by the first latching part relative to the hollow guide sleeve, during travel motions of the hollow guide sleeve in the second control body. 
 
     
     
       7. The valve device according to  claim 1  wherein
 the first control body is preloaded by an energy accumulator in ae direction of the first blocking position and/or movable from the first blocking position into the first release position against a force of the energy accumulator by a rod drive. 
 
     
     
       8. The valve device according to  claim 5  wherein
 the hollow guide sleeve, when blocked by the first latching part for the travel motion in a second control body in at least one direction of travel, acts on the first valve piston such that the first valve piston is lifted off a valve seat of the first valve piston against the force of an energy storage preloading the first valve piston into a closed position of the first valve piston. 
 
     
     
       9. The valve device according to  claim 7  wherein
 the rod drive extends centrally through the first valve piston. 
 
     
     
       10. The valve device according to  claim 5  wherein
 the hollow guide sleeve, the first valve piston and a second valve piston movable longitudinally in the valve housing between positions separating at least two of the fluid ports from one another or interconnecting at least two of the fluid ports as a function of a travel position of the second valve piston are guided for travel relative to each other along a longitudinal axis of the first valve piston and the second valve piston. 
 
     
     
       11. The valve device according to  claim 1  wherein
 the first control body has, at least sectionally, a cylindrically formed outer diameter being guided in a hollow guide sleeve, when the first control body is disposed in the first blocking position, and limiting motion of the first latching part in such that the first latching part is held blocked in the latching position. 
 
     
     
       12. The valve device according to  claim 1  wherein
 the first control body is preloaded by an energy accumulator in a direction of the first blocking position and each of the first valve piston and of a second valve piston movable longitudinally in the valve housing between positions separating at least two of the fluid ports from one another or interconnecting at least two of the fluid ports as a function of a travel position of the second valve piston. 
 
     
     
       13. The valve device according to  claim 1  wherein
 a second valve piston is movable longitudinally in the valve housing between positions separating at least two of the fluid ports from one another or interconnecting at least two of the fluid ports as a function of a travel position of the second valve piston, the first and second valve pistons having the first latch and a second latch, respectively, on end faces thereof facing away from each other, a second latch being connected to the second valve piston detachably fastening the second valve piston in one of travel positions of the second valve piston; and 
 first and second actuators are connected to the first and second latches, respectively, such that when the first actuator is activated to move the first latch from an unlatched state thereof to a latched state thereof, the second actuator is activated to move the second latch from an unlatched state thereof to a latched state thereof, and vice versa. 
 
     
     
       14. The valve device according to  claim 13  wherein
 each of the first and second actuators, when activated, acts at least on the first and second valve pistons, respectively, and on the first and second latches, respectively. 
 
     
     
       15. The valve device according to  claim 14  wherein
 the second latch having a second latching part movable into and out of a second latching position and having a first control body movable independently of the second valve piston, the first control body of the second latch being movable to a second blocking position preventing the second latching part disposed in the second latching position from leaving the second latching position by blocking the second latching part; and 
 the first and second latches are operatively interconnected by at least one part of a rod drive disposed therebetween, the rod drive being in contact with the first control bodies of the first and second latches. 
 
     
     
       16. The valve device according to  claim 1  wherein
 a first travel distance of the first hollow guide sleeve along a travel path from an end position of the first hollow guide sleeve furthest from the first valve piston to an action position of the first hollow guide sleeve acting for a first time on the first valve piston on the travel path is greater than or equal to a second travel distance of the first hollow guide sleeve from the action position acting for the first time on the first valve piston to first sleeve blocking position. 
 
     
     
       17. The valve device according to  claim 13  wherein
 an energy storage extends between the first and second valve pistons and biases the first and second valve pistons away from each other. 
 
     
     
       18. The valve device according to  claim 13  wherein
 the first and second valve pistons reach closed positions thereof at a first and second valve seats in directions away from each other. 
 
     
     
       19. The valve device according to  claim 18  wherein
 the first and second valve pistons are accommodated in a replaceable insert housing part on which the valve seats are formed. 
 
     
     
       20. A valve device, comprising:
 a valve housing having fluid ports therein; 
 a first valve piston movable longitudinally in the valve housing between positions separating at least two of the fluid ports from one another or interconnecting at least two of the fluid ports as a function of a travel position of the first valve piston; 
 a first latch connected to the valve piston detachably fastening the first valve piston in one of travel positions of the first valve piston, the first latch having a first latching part movable into and out of a first latching position and having a first control body movable independently of the first valve piston, the first control body being movable to a first blocking position preventing the first latching part disposed in the first latching position from leaving the first latching position by blocking the first latching part; and 
 a rod drive extends centrally through the first valve piston. 
 
     
     
       21. A valve device, comprising: a valve housing having fluid ports therein; a first and second valve pistons movable longitudinally in the valve housing between positions separating at least two of the fluid ports from one another or interconnecting at least two of the fluid ports as a function of travel positions of the first and second valve pistons; first and second latches connected to the first and second valve pistons, respectively, on end faces thereof facing away from each other detachably fastening the first and second valve pistons, respectively, in one of travel positions of the first and second valve pistons, the first and second latches having first and second latching parts, respectively, movable into and out of first and second latching positions and each having a first control body movable independently of the respective first or second valve piston, each of the first control bodies being movable to a first blocking position preventing the respective first or second latching part disposed in the first latching position from leaving the first latching position by blocking the first latching part; and first and second actuators are connected to the first and second latches, respectively, such that when the first actuator is activated to move the first latch from an unlatched state thereof to a latched state thereof, the second actuator is activated to move the second latch from an unlatched state thereof to a latched state thereof, and vice versa. 
     
     
       22. The valve device according to  claim 21  wherein
 each of the first and second actuators, when activated, acts at least on the first and second valve pistons, respectively, and on the first and second latches, respectively. 
 
     
     
       23. The valve device according to  claim 22  wherein
 the first and second latches are operatively interconnected by at least one part of a rod drive disposed therebetween, the rod drive being in contact with the first control bodies of the first and second latches. 
 
     
     
       24. The valve device according to  claim 21  wherein
 an energy storage extends between the first and second valve pistons and biases the first and second valve pistons away from each other. 
 
     
     
       25. The valve device according to  claim 21  wherein
 the first and second valve pistons reach closed positions thereof at a first and second valve seats in directions away from each other. 
 
     
     
       26. The valve device according to  claim 25  wherein
 the first and second valve pistons are accommodated in a replaceable insert housing part on which the valve seats are formed.